Every state Medicaid program has recently implemented cost saving mechanisms in an effort to contain rapidly growing expenditures. However, little is known about how these strategies, including increased cost sharing, restricted eligibility, and reduced benefits, affect insurance coverage, health care access, and health outcomes of low-income individuals. Within the Oregon Health Plan (OHP), the recent implementation of program changes like those enacted in other states has created a natural experiment ideal for examining the impacts of such Medicaid policy changes. The specific aim of the proposed study is to identify and assess the impacts of recent Medicaid program changes along 5 outcome dimensions: 1) Disenrollment and subsequent re-enrollment in OHP or other types of insurance, 2) Access to health care, mental health care, and prescription medications, 3) Utilization of primary care, urgent care, and emergency department services, 4) Financial status, and 5) Health outcomes. Using a prospective cohort design, a group of 1378 OHP beneficiaries who experienced changes in their benefits, premiums and co-pays will be compared with a similar group of 1405 beneficiaries who were enrolled during the same time period but experienced no changes. Building on existing baseline and 6-month follow-up surveys, the proposed study will add the third and final wave of surveys needed to assess the short and long term impacts of Medicaid policy changes on a stable cohort of individuals without the inherent limitations of cross-sectional data. The application's long-term objective is to provide policy relevant research findings about the impact of health care financing and delivery strategies on vulnerable populations and to contribute cost-effective solutions for improving the efficiency and quality of health care. Access to affordable health insurance and health care, particularly for low income populations, is currently 1 of the most pressing public health issues. [unreadable] [unreadable] [unreadable]